Arc chute



IEINVENTOR.

aftmey 5 Sheets-Sheet l C. J. RIDGLEY ARC CHUTE June 23, 1953 Flled May 20, 1950 5 Sheets-Sheet 2 C. J. RIDG LEY ARC CHUTE June 23, 1953 Filed May 20, 1950 d JNVfTNTO ay 9 '9 W 'YFM altomw ARC CHUTE 5 Sheets-Sheet 3 Filed May 20, 1950 INVENTOR (bk/mums J #10616) Patented June 23, 1953 CHUTE Cornelius I. Ridgley, Philadelphia, Pa., assignor' to I-T-E Circuit Breaker Company, Philadebphia, Pa., a corporation of Pennsylvania Application May 20, 1950, Serial No. 163,216

My present invention relates to circuit breakers, and more particularly to are chutes incorporated therein for the purpose of rapidly extinguishing any are which may be formed on the occurrence of a circuit interruption.

Still more specifically, my invention is directed to the addition of a cross-insulating plate are suppressor to a conventional parallel plate are chute.

Particularly in the case of high voltage" D. C. arcs, the arc has a tendency to expand within the conventional arc chute if there is sufficient magnetic force directed in the proper direction, and the arc may tend to exist outside the arc chute until the circuit to the supply feeding the fault current has been opened by other means. The utilization of the cross plates as sists in reducing the effects of the stored energy of the system without excessive burning.

Thus, the primary object of my present invention is the provision of a novel are chute adapted to rapidly extinguish the arc, particularly in direct current applications of a circuit breaker.

Another object of my invention is the provision of cross insulating plates above the spaced parallel plate are chute in order to assist in the extinction of the arc.

Still another object of my invention is the provision of a, novel chamber adjacent the arc chute in order to guide the escaping arc gases.

The foregoing and many other objects ofmy invention will become apparent in the following description and drawings in which Figure 1 is a partially schematic side view of a circuit breaker embodying my novel are chute.

Figure 2 is a front view of my novel circuit breakers arc extinguishing means.

Figure 3 is a side view corresponding to that of Figure 1 showing a modified arrangement of arc extinguishing plates as exhibited in Figures 1 and 2. e

Figure 4 is a front view of the modified form of Figure 3.

Referring first to Figures 1 and 2, the circuit breaker there shown is provided with an upper back connection stud H, a lower back connection stud schematically shown at l2, stationary contacts 13 and I4 bridged by the movable bridging contact [5.

The bridging contact I5 is operated by the toggle member [1 comprising the links 18 and [9, link I8 being pivotally connected by pin 20 to the bridging contact I5, link. [9 being pivotally connected by the pin 2| to thebellcrank 7 Claims. (Cl. 200- 144) latch lever 22 which in turn is pivotally mounted on, pin 23.

Toggle member l! is so arranged that its knee pin 25 is subject to upward opening force by the tension spring 26. Link 21 connected to the solenoid plunger 28 of the closing electromag netic solenoid 29 may be pulled down by energization of the closing solenoid 29 to close the circuit breaker.

The bell crank latching lever arm- 30 is pivotally mounted at 31 and is provided with the latching surface 32 engaging the latch pin 33 mounted on the bell crank latch member 22.

Extension 35 of the bell crank lever arm 30 is arranged to be engaged by armature 36 of the tripping device 31 which is energized from coil 38 electrically integral with the circuit of the back connection stud l2.

When the current reaches a predetermined value, armature 36 of the tripping device 31 is moved upwardly so as to rotate lever 30 clockwise thereby disengaging the latching surface 32 from the latch pin 33 and permitting the toggle l! to collapse upwardly opening the circuit breaker.

Where the movable contact [5 is a bridged contact, then the circuit breaker opens in such manner that the contact is pivotally maintained at stationary contact 14 until the resultant, arc is totally extinguished. v

Preferable, bridging member 15 is a contact arm pivotally mounted at [4 so that the only place where an electric arc is drawn is at stationary contact [3.

The are is transferred upwardly by means. familiar to those versed in the art to the moving: arcing. contact 40 which cooperates with the stationary arcing contact 4| on the back connection stud ll.

As the contacts separate, the electric arc is: transferred to the uppermost arcing contact 42 which connects the blow-out coil 43 in series with the arc, thereby providing a blow-out effect in a manner well known in the art and requiring no further description here.

The are is then forced electromagnetically up on the-arc horns 45 and 46 into the composite arc chute 41. The are chute 41 is generally of the type described in-PatentsNos. 2,390,735; 2,311,690; 2,348,228; 2,311,701; 2,375,328; and 2,338,715.

The arc chute 41 comprises a plurality of spaced arc extinguishing insulating plates 50 supported between insulating side plates 5| and spaced from each other by appropriate bushings 52 on the connecting and integrating bolts 53. The are extinguishing plates 50 are mounted pan allel to the axis of the arc formed between the uppermost arcing contact 42 and the moving arc contact 40. These plates 5|] are effective in extinguishing the are by virtue both of its cooling properties and of its longitudinal sectionalizing of the ionized gas formation within the chute 41.

My invention further contemplates, as previously pointed'out, the utilization of an auxiliary arc chute member 55 comprising a plurality of insulating plates 56 mounted between a pair of end plates 51, 51 and held in position by a plurality of bolts 58, 58 on which are mounted separate insulating bushings 59, 59 in order to space the insulating plates 56 from each other.

In order to permit the arc gases rapidly to leave the top of the arc chute 41-and enter the upper auxiliary arc chute 55, I have found it desirable and in fact necessary for maximum efficiency that the insulating cross plates 56 of auxiliary arc chute 55 be spaced somewhat, above the top of the arc chute 41 in orderto provide an open area 60 into which the arc. gases may rise preliminary to their entry into the auxiliary arc chute.

Preferably this open space is obtained by shaping each plate 56 so that it has a lower edge 62 to be positioned just above the top of arc chute 41. The lower edge 62 connects with inclined edge 63 and then connects, with raised lower edge 64 as shown particularly in, Figure 2 to create the open space.

By reversing adjacent plates 56, a, V-shaped chamber 60 as viewed from the front is provided; as shown in Figure; 2 between the. upper auxiliaryarc chute 55 and, the lower arc chute 41. The same result can be achieved by placing a V-shaped notch in each of the plates 56. A better flow of arc, gases is obtained by the reversed arrangement shown.

'Ifhe auxiliary arc chute member 55 affords a chopping-up of the arc lengthwise as said are progressively enters the auxiliary chute 55. The chopping-up of this arc, is accomplished more efficiently with the lower potential gradient of the greatly extended arc length. The cross plates 55 also afford more, efficient cooling at he 8. 36 e iclsn The auxiliary arc chutes 55'as shown in Fig.- ure; in adjacent circuit breakers, are, covered oyer and fully enclosed at the. top by. the closing plates, "liiwhich are preferably of insulating material.

The are extinguishing gases are, therefore, directed laterally through the plates 55 of the auxiliary arc chute 5%} into the downwardly directed exhaust cl-iarnber 12, "II on each side as shown in Figure 2.

Thus, in a two-pole arrangement as shown in Figure'Z, the arc gases from pole I pass upwardly through the arc chute 41 to be cooled and possibly extinguished thereby and then pass upwardly through the cross, platearc chute-55 further to becooled and extinguished thereby.

Ihe arc gases are then' directed to the left for pol I and downwardly in chamber H to be further cooled prior toytheir exit. into the, atmos.- phere.

Similarly, for pole II, the exhaustfrom the auxiliary arc chute 55 is to the right, into chamber 12 and then downwardly.

Variousarrangements of arc chute may be used. Thus, asshown in the slightly modified form of lifigure Ii, the principal arc chute. I41

4 is relatively smaller while the auxiliary arc chute I55 is also relatively smaller.

The plates I56 thereof in this case all have a linear lower edge, but plates I56a have a lower edge which terminates at a level higher than that of plates I561) to produce the stepped arrangement shown in Figure 3, thereby providing a plurality of small chambers I60 in which the arc gases may have free passage from the lower arc chute to the upper arc chute. The exhaust to the left or right is in the same manner as that previously described.

Actually, the relative dimensions shown in Figures 3 and 4 are preferably dimensions for good operation of an. arc chute in the field and for the purpose herein described.

Thus, in an actual unit intended to have an interrupting capacity of 15,000 amperes at 1000 volts,'the.lower arc chute I41 is preferably ten inches high, While the upper arc chute I55 is preferably of the order of four inches high.

By this means, therefore, a simplified are extinguishing device is provided which will ensure that especially in the case of a direct current unit the arc, should it leave the lower arc chute 41 or I41, will be fully extinguished in the upper arc chute 55 or I55 so that the flame or heat of an actual arc will not rise above or out of the composite arc chute.

In the foregoing I have described my invention solely in connection with specific illustrative embodiments thereof. Since many variations and modifications of my invention will now be obvious to those skilled in the art, I prefer to be bound not by the specific disclosures herein contained but only by the appended claims.

I claim:

1. In a circuit breaker having a pair of cooperable contacts, one of said contacts being movable with respect to the other of said contacts, an arc chute comprising a first plurality of spaced parallel insulating plates mounted parallel to the axis of the arc formed between the contacts when they separate, said plates forming a notch at their lower edges in which relative movement of said cooperable contacts occurs, an auxiliary arc chute comprising a second plurality of par allel insulating plates extending transversely of said first parallel plates for lengthening the arc path, the lower edges of at least some of said second plates being spaced above the top edges of. said, first plates, a portion of the lower edges of each of said second plates being inclined to meet another lower portion of its associated plate so that when said second inclined portions of plates are inverted with respect to each other, a space transverse to the parallel direction of said first plates is formed, a closing insulating plate across the top of said second plates for fully enclosing thetop of said auxiliar arc chute and vertically extending exhaust chambers for each side of. said space. for directing exhaust gases downwardly and opening into the atmosphere.

2.. In a circuit breaker having a pair of cooperablecontacts, one of said contacts being movable withrespect to the. other of said contacts, an arc chute, comprising a first plurality of spaced parallel insulating plates mounted parallel to the axis of the are formed between the contacts when they separate, an auxiliary arc chute. comprising a second plurality of parallel insulating plates extending transversely of said firstparallel plates for lengthening the. arc. path, the. lower. edges of at least some of said second plates being spaced above the top edges of said first plates, a portion of the lower edges of each of said second plates being inclined to meet another lower portion of its associated plate so that when said second inclined portions of plates are inverted with respect to each other, a space transverse to the parallel direction of said first plates is formed, a closing insulating plate across the top of said second plates for fully enclosing the top of said auxiliary arc chute and vertically extending exhaust chambers for each side of said space for directing exhaust gases downwardly and opening into the atmosphere.

3. In a circuit breaker having a pair of cooperable contacts, one of said contacts being movable with respect to the other of said contacts, an arc chute comprisin a first plurality of spaced parallel insulating plates mounted parallel to the axis of the are formed between the contacts when they separate, said plates forming a notch at their lower edges in which relative movement of said cooperable contacts occurs, an auxiliary arc chute comprising a second plurality of parallel insulating plates extending transversely of said first parallel plates for lengthening the arc path, the lower edges of at least some of said second plates being spaced above the top edges of said first plates, to form a space transverse to the parallel direction of said first plates, a closing insulating plate across the top of said second plates for fully enclosing the top of said auxiliary arc chute and vertically extending exhaust chambers for each side of said space for directing exhaust gases downwardly and opening into the atmosphere.

4. In a circuit breaker having a pair of cooperable contacts, one of said contacts being movable with respect to the other of said contacts, an arc chute comprising a first plurality of spaced parallel insulating plates mounted parallel to the axis of the are formed between the contacts when they separate, an auxiliary arc chute comprising a second plurality of parallel insulating plates extending transversely of said first parallel plates for lengthening the arc path, the lower edges of at least some of said second plates being spaced above the top edge of said first plates to form a space transverse to the parallel direction of said first plates, a closing insulatingplate across the top of said second plates for fully enclosing the top of said auxiliary arc chute and vertically extending exhaust chambers for each side of said space for directing exhaust gases downwardly and opening into the atmosphere.

5. In a circuit breaker having a pair of cooperable contacts, one of said contacts being movable with respect to the other of said contacts, an arc chute comprising a first plurality of spaced parallel plates mounted parallel to the axis of the are formed between the contacts when they separate, said plates forming a notch at their lower edges in which relative movement of said cooperable contacts occurs, an auxiliary arc chute comprising a second plurality of parallel plates extending transversely of said first parallel plates for lengthening the arc path, the lower edges of at least some of said second plates being spaced above the top edges of said first plates, a portion of the lower edges of each of said second plates being inclined to meet another lower portion of its associated plate so that when said second inclined portions of plates are inverted with respect to each other, a space transverse to the parallel direction of said first plates is formed, a closing plate across the top of said second plates for fully enclosing the top of said auxiliary arc chute and vertically extending exhaust chambers for each side of said space for directing exhaust ases downwardly and opening into the atmosphere.

6. In a circuit breaker having a pair of cooperable contacts, one of said contact being movable with respect to the other of said contacts, an arc chute comprising a first plurality of spaced parallel plates mounted parallel to the axis of the are formed between the contacts when they separate, an auxiliary arc chute comprising a second plurality of parallel plates extending transversely of said first parallel plates for lengthening the arc path, the lower edges of at least some, of said second plates being spaced above the top edge of said first plates to form a space transverse to the parallel direction of said first plates, a closing plate across the top of said second plates for fully enclosing the top of said auxiliary arc chute and vertically extending exhaust chambers for each side of said space for directing exhaust gases downwardly and opening into the atmosphere.

7. In a circuit breaker having a pair of cooperable contacts, one of said contacts being movable with respect to the other of said contacts, an arc chute comprising a first plurality of spaced parallel insulating plates mounted parallel to the axis of the are formed between the contacts when they separate, said plates forming a notch at their lower edges in which relative movement of i said cooperable contacts occurs, an auxiliary are chute comprising a second plurality of parallel insulating plates extending transversely of said first parallel plates for lengthening the arc path, the lower edges of some of the second plates being closer to the top edges of the first plates to form a plurality of spaces transverse to the parallel direction of said first plates, a closing insulating plate across the top of said second plates for fully enclosing the top of said auxiliary arc chute and vertically extending exhaust chambers for each side of said space for directing exhaust gases downwardly and opening into the atmosphere.

CORNELIUS J. RIDGLEY.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,259,005 Scott, Jr Oct. 14, 1941 2,293,452 Boehne Aug. 18, 1942 2,443,521 Scott, Jr June 15, 1948 2,460,727 Atwood et al Feb. 1, 1949 FOREIGN PATENTS Number Country Date 564,050 Great Britain Sept. 11, 1944 

